Pretty logical, by far the hardest park to go yard in, or score for that matter. Angels have a decently tough park, but I think there's might actually be more a team oriented approach towards one run innings than the Padres.
Padres Second Since 2005, the team with the most ROAD wins in major league baseball in which they scored a maximum of one run in any inning is The Chicago White Sox with 27. The Padres are second with 26.
Perhaps with a better pitching staff they play for the lone run rather than the big inning (perhaps moving the runners up by sacrificing or hitting to the right side of the field)???
The SDQL is simply:
RMAX=1 and A and W and season>=2005 and team